SU1245367A1 - Working roll unit for rolling corrugated strip - Google Patents

Description

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15

The invention relates to the field of metal forming, in particular, to rolling mill production, and can be used in countries for rolling sheets, in particular corrugated.

The aim of the invention is to prevent the formation of cracks and tears of the corrugations.

FIG. 2 shows a work roll assembly for rolling a corrugated strip; FIG. in fig. 2 - deformation center.

The site contains work rolls, made by teams, consisting of profiled-deformed sections of width D and non-finished idle sections 2, which are installed with saaqpoM on shafts 3 and 4. The shaped sections 1 of one roll have grooves, made in a cyanic form, 20 The non-profiled deforming areas I of the other, roll have protrusions corresponding to those of the first roll, 1a of the first and second rolls, there are non-profiled 25 blank sections 2, which have gaps between shafts 3 and 4 of the rolls and between deformers worlds sites 1 and 2 rolls. The shafts 3 and 4, on which: the rolls are full of ease, are placed in the rolling roller subtype 5 and are driven into rotation from the electric motor through the gearbox.

The formation of two corrugations, the billet, is carried out by deforming the first and second rolls,. .

245367.

mi), then this leads to a difference in line speeds. A more rational redistribution of contact stresses reduces tensile stresses in places of corrugation, which become less than fracture stresses, thus avoiding cracks along the length of the corrugations. Pa it can be affected; By varying the radii R and R, the depth (height) of the caliber of the deforming sections h and the angle di, which determine the junction points of the radii RI and RK. This is not enough to avoid the formation of cracks and breaks, since these parameters do not directly affect the value rzorobleni flat part of the workpiece. It is also advisable to separate the deforming and holos1 plots.

rolls, which leads to a rational distribution of contractual stresses. The width of the profiled sections & associated functional dependence with the values of the radii, whiskers of protrusions (recess) of the calibers of the deforming sections R, and R ,,, the height of the protrusion (depth of the depth) h, the angle of the radius of the tip ot, the length of the barrel of the work rolls L.

The mutual influence of sections 1 and P during rolling in conventional rollers is manifested at a distance of not less than 2-3 gauge widths under the protrusions on each side, therefore ui is 4-6 widths of capybras, which will reduce the effect section G for change and stress state of section II, especially in zones L and B (Fig. 1).

This goal is achieved by eliminating or substantially weakening the mutual influence of the flat I and profile IT parts of the strip on each other by reducing the inequality of stretch and linear velocity over the cross section, eliminating the influence of the middle part of the rolls on the shaping and reducing the size of the stretch joints in zones L and B (especially in zone L).

The width of the work rolls L depends on the radii R and R, the depth (height) of the caliber of the deforming sections h, angle., Defined u1; g, its junction point of the radii R, the barrel rolls L,

Since there is a significant difference in the rolling radii on the bottom of the gauge On a roll with a recess (at the top of the gauge on a roll with a protrusion R, length

rolls, which leads to a rational distribution of contractual stresses. The width of the profiled sections & associated functional dependence with the values of the radii, whiskers of protrusions (recess) of the calibers of the deforming sections R, and R ,,, the height of the protrusion (depth of the depth) h, the angle of the radius of the tip ot, the length of the barrel of the work rolls L.

The mutual influence of sections 1 and P during rolling in conventional rollers is manifested at a distance of not less than 2-3 gauge widths under the protrusions on each side, therefore ui is 4-6 widths of capybras, which will reduce the effect section G for change and stress state of section II, especially in zones L and B (Fig. 1).

Analyzing the geometry of the deformation zone, we obtain the following formula, which allows us to determine the optimal width of the deforming sections of the workers.

A (4-6) 2 (R, sino (+2 (), (1)

at Usol L.,

where L is the length of the roll barrel;

width of professional sections of the bandage; the radii that form the cylindrical surface of the protrusions. deepen the profiled parts of the bandage;

height and depth of protrusions and recesses;

L PM and R h

ot is the angle of the radius top of the recess.

In order to reduce the distortion of the flat part of the workpiece and to redistribute the contact stresses, the non-profiled part of the working tool must, along with smoothing the flat part of the workpiece, ensure the slippage over the surface of the sheet.

The middle part of the rolls is idle with a gap caused by the need to ensure the rolls slip on the sheet surface and reduce the distortion of the flat part of the workpiece. Therefore, the gap is made of a certain size and filled with elastic wear-resistant filler 6, for example polyurethane.

To reduce the coefficient of friction between the elastic filler and the inner surface, the non-profiled parts of the roll serve lubricant, which allows the non-profiled part to slip along the elastic wear-resistant coating, and the elastic coating creates elastic spring conditions, which improves the smoothing condition, reduces the distortion of the workpiece, reduces the noise level but does not interfere with the prevailing deformation carried out by the core sections of the working collective rolls.

An example. The barrel length of the roll sets is 250 mm; the roll diameter of the non-profiled part is 120 mm. Five sets of rolls with various pa- rammeters (table).

The studies were carried out on a sheet blank of Art. 3 with a thickness of 2-2.5 mm, a width of 250 mm and a length of 0.5–0.7, 7 m. Instrument parameters: E, mm; R h 9.5 mm; Number of corrugations 2, for prefabricated rolls

110

 The distortion of the sheet,% 0,65 0,38 0,40 0,38 0,45 0,28 0,21 0,32 0,35

to

15

20 25

thirty

35

40

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did not change, which allowed us to reveal the optimal width of the deforming sections and determine the size of the gap filled with elastic filler.

The use of all-metal rolls does not allow to achieve the desired result even when using different variations of tool parameters, since the use of rigidly interconnected deforming roller areas does not provide the necessary redistribution of contact stresses and frictional forces. The use of work rolls 1 with a large extent of deforming sections does not allow to achieve the desired effect due to the proximity of the deformation conditions in such rolls to the deformation conditions in all-metal rolls.

The most favorable results were achieved when using combined rolls with the width of the deforming section u70-80 mm (, 1), the size of the gap a 5-6 mm (a / DJ ratio, 0.15).

Calculations by the formula (I): the optimal width of the deforming section is U74-91 mm.

The present invention may be used in pipe production for sheet production. corrugated billet for self-compensating pipes used in the construction of trunk pipelines.

A four-stand mill for the production of a corrugated billet for spiral-seam self-compensating tubes is adopted as the base object.

The implementation of the proposed invention will provide an economic effect of more than 50,000 rubles. in year. 100

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60

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Gaps, Gaps, Gaps and you and you and cracks, cracks, cracks in our zones Li

Table continuation.

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71 31 79 61

FIG ..

Claims (1)

WORKING ROLLER ASSEMBLY FOR ROLLING A CORRUPTED STRIP, containing a bandage mounted on the axis, having smooth and shaped sections, the last of which ^; made with protrusions and recesses, characterized in that, in order to prevent the formation of cracks and ruptures of the corrugations, the bandage is made compound by the number of smooth and profiled sections, and the smooth sections are mounted on the axis with the ability to move relative to it and the profiled sections, the protrusions and recesses are cylindrical surface, and the width A of the profiled sections is 4 = (4-6) 2 [R sind + 2 (R „+ £ ^ ½)] ^{1 2} tg.ot under the condition b> 2d, where L is the length of the shaft barrel; R, and R ₂ are the radii forming the cylindrical surface of the protrusions and recesses of the profiled sections of the bandage; h ‘- the height and depth of the protrusions and recesses; ot is the angle of the radius peak of the recess. SU 1245367 A1